What are the correct codes for billing a CBC with and without differential?


Billing for a complete blood count (CBC) with or without a differential has historically been the focus of audits conducted by the Department of Health & Human Services Office of Inspector General (OIG). It is again being identified as an issue in post-payment reviews.

If the physician has ordered only a CBC with no mention of a differential, the correct code is 85027—blood count; complete (CBC), automated (Hgb, Hct, RBC, WBC and platelet count). Even if a lab has a policy in place to always perform an automated differential with a CBC regardless of what is included in the request/order, the laboratory may bill only for what is ordered in the patient’s medical record.

This question was answered in the 2018 edition of our Coding Essentials for Laboratories. For more hot topics relating to laboratory services, please view our store, or call us at 1.800.252.1578 ext. 2.


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